An electronic card, in which an antenna is incorporated, as well as a process for the production of such a card are known from the document DE 197 32 645. In a particular embodiment of this process shown in part in FIGS. 3A-3C and 4A-4C, the antenna is formed by a plane coil with a metal wire of circular section. In general, the diameter of such a wire is very small (100 to 150 microns). In order to connect the two ends of the antenna to an electronic unit, it is firstly provided that two holes are made in the card body to a depth corresponding to a median plane of these two ends, and these two holes have a diameter that is substantially equal to that of the antenna wire. The two holes are then filled with a conductive glue or a solder material. The manner in which the conductive glue or the solder material are applied into the two holes of small diameter is not explained anywhere in this document DE 197 32 645. This step of the process is not in fact obvious. How to insert the glue or the solder material into such small holes in an industrial production? Firstly, there is a question of the precise positioning of a nozzle or needle serving to apply the glue or solder material. Then, how to allow the air that is initially present in the holes to escape during the insertion of the glue or the solder material? The answer to this question is important, since an electrical connection must be assured via these holes. A person skilled in the art will not find an answer in the document in question and in fact the answer is not obvious, since air is generally trapped by the glue or the solder material inserted through the aperture. A kind of plug is thus formed that traps the air at the bottom of each hole and the rest of the material applied then spreads over the plane surface on the periphery of the holes. It is clear that such a situation is particularly disadvantageous when the holes are close because of the increased risk of short-circuiting. Hence, a person skilled in the art will consider the configuration of an electronic card according to FIGS. 3A-3C and 4A-4C of the document DE 197 32 645 very difficult, or indeed practically impossible, to implement.
An electronic card is known from document WO 97/34247, wherein the solder material provided between the respective contact pads to form the electrical connections is inserted into an adhesive film. The solder material is incorporated in particular into apertures formed in this adhesive film (see FIGS. 8 to 10), which is then applied to a shoulder arranged in the cavity provided for an electronic module in such a manner that the apertures filled with solder materials are aligned on internal contact pads that are visible on the surface of the shoulder. The electronic module is arranged such that the solder material also faces contact pads arranged on the inside face of an insulating support of this module. Finally, the glue is activated and the solder material is melted by a supply of heat through the insulating support. It will be noted that the application of solder material in the apertures of an adhesive film before this is assembled on the electronic module or card body poses problems of production, since it is not obvious how to hold the solder material in the apertures of the adhesive film until the electronic module is assembled with the card body. Thus, in a variant it is provided to introduce conductive particles into an adhesive film into the zones provided for the solder joints.